Whoa! 1,763 3rd party LOB server apps have been integrated in to Azure AD already…

You can either build your own LOB app and integrate it in to Azure AD. Or if you already have one of 1,763 that have already been integrated, you can use that too.

Integrating the app in to Azure AD means you can sign in using credentials stored in Azure AD – but most importantly, if you have AD on-premises, you can set up federation between the 2 and get the benefit of single-sign-on. One scenario would be:

You log in at 9am as usual. You probably go and grab a coffee then when you get back to your desk, no doubt email is the first app you open. You aren’t prompted for credentials (if it’s Outlook/Exchange). Maybe somebody has sent you a link to a doc that lives in SharePoint – you aren’t prompted. You decide you want to print the doc – you aren’t prompted. Let’s say you now need to access one of the apps (one of the 1,763 in the screenshot above). You just click on the link and bingo – you’re logged in to the app. Just as if it was a piece of your core infrastructure on-premises.